Array comprising row of electro-optical elements and associated row of semiconducting microcircuits located on adjoining faces of a parallelepipedal slab

ABSTRACT

A solid material in shape of a parrallelpiped on carries on one of its major surfaces a set of electric circuits, each connected to an electro-optical element for energy conversion between electric and radiative modes. The electro-optical elements are arranged in a row near a major edge of the parallelpiped on in such a manner that said radiative mode is directed perpendicular to said edge thus defining a row of points for light emission, reception or modulation along said edge. A set of such parallelpiped on is stacked to provide a two-dimensional array of such points for light emission, reception or modulation.

l 1, Unite n States stem [72] Inventor Kurt Lehovec ll Woodlmwn Drive,Williamstown, Mess. 01267 [21] Appl. No. 14,362 [22] Filed Feb. 26, 1970[45] Patented Dec. 28, 1971 [54] ARRAY CGMPRISING ROW 0F ELECTRO-OPIICAL ELEMENTS AND ASSOCIATED ROW 01F SEMICONDUCTING MICROCIRCUITSLOCATED ON ADJOINING FACES OF A PARALLELEPIPEDAL SLAB 15 Claims, 11Drawing Figs.

[52] US. Cl 250/208, 250/213 R, 250/217 SS, 250/220 M, 315/169, 350/ 160[51] Int. Cl ..H01j 31/50, HOlj 39/12, HOSb 37/00 [50] Field of Search250/220 MX, 208, 209, 213, 217 SS; 315/169; 317/235 N; 350/160 PrimaryExaminer.lames W. Lawrence Assistant Examiner-T. N. Grigsby ABSTRACT: Asolid material in shape of a parrallelpiped on carries on one of itsmajor surfaces a set of electric circuits, each connected to anelectro-optical element for energy conversion between electric andradiative modes. The electro-optical elements are arranged in a row neara major edge of the parallelpiped on in such a manner that saidradiative mode is directed perpendicular to said edge thus defining arow of points for light emission, reception or modulation along saidedge. A set of such parallelpiped on is stacked to provide atwo-dimensional array of such points for light emission, reception ormodulation.

PATENTED BEC28 I971 SHEET 1 [1F 4 ARRAY COMPRISING ROW OIFELECTRO-OPTICAL ELEMENTS AND ASSOCIATED ROW OF SEMICONDUCTINGMICROCIRCUITS LOCATED ON ADJOINING FACES OF A PARALLELEPIPEDAL SLABBACKGROUND OF INVENTION This invention deals with the physicalarrangement of electro-optical components and of associated electricalcircuitry in electro-optical structures. In particular, this inventiondeals with the arrangement of large numbers of identical electroopticalelements, each combined with its own electric circuitry into one ortwo-dimensional arrays.

Electro-optical structures are hereafter defined as structurescomprising electric circuitry functionally connected withelectro-optical elements for purpose of generation of light,transformation of light into electric signals or modulation of light inconjunction with the above-mentioned elements may or may not be part ofthese structures.

Two-dimensional arrays of electrically stimulated light emitters arewell known for display panels. Two-dimensional arrays of photocells arewell known for conversion of optical images into television signals. Inmany cases, these electro-optical elements are activated in sequence bya clock circuit and electrical processing of the optical signal emittedor received occurs in a stage common to all elements.

Provision of each electro-optical element with its own electricalprocessing stage has definite advantages. For instance, amplification ofa weak electrical signal immediately adjacent to a photocell suppressesnoise pickup of cross talk" which may enter during transport ofnonamplified weak signals to clock circuitry in the case thatamplification occurs in a common stage after the clock circuit.

Hitherto, it has not been practical to provide each electroopticalelement with its individual electrical circuits for the followingreasons: First, cost appeared prohibitive until recently, whenmicrocircuit technology became available. Second, space considerationappeared to exclude such an arrangement, considering thatelectro-optical elements are frequently spaced only about a mi] apart inan array.

Electro-optical arrays such as used for television involve a very largenumber of identical elements, of the order of 1,000,000, and failure ofonly a few of these elements leads to total reject. My invention teachesthe assembling of twodimensional arrays from a set of linear arrays,which enables pretesting, and rejection of smaller entities if foundfaulty, thereby saving cost.

It is an objective of this invention to teach a new and advantageousarrangement for an array of electro-optical elements at close spacing,each comprising its associated electrical circuitry.

It is a further objective of this invention to teach a new andadvantageous assembly of linear rows of electro-optical elements, eachwith associated electric circuitry, into two-dimensional arrays.

SUMMARY OF THE INVENTION Briefly, the invention consists in arrangingthe electro-optical elements at or near one of the small faces of arectangular slab with planar microcircuitry associated with each of saidelectro-optical elements at an adjoining major face of said slab.Typically, a linear row of electro-optical elements may be arrangedalong an edge of a slab, the associated circuitry to each element on themajor face of the slab and extending in direction normal to said edge.Several such slabs can be stacked side by side with suitable insulationbetween them, thus providing a two-dimensional array of electro-opticalelements. Contacts can be conveniently located at a major edge spacedfrom that edge near which the electro-optical elements are located, withthe second common contact being the bulk of the conducting slab.

BRIEF DESCRIPTION OF DRAWINGS FIG. I shows a monolithic electro-opticalstructure according to this invention for transforming incident lightinto electnc current.

FIG. 2 shows the prior art circuit pertaining to the structure of FIG.1.

FIG. 3 shows a monolithic electro-optical structure according to thisinvention for generation of light flashes from a linear array of points.

FIG. 4 shows a hybrid electro-optical structure according to thisinvention for generation of light from a linear array of points.

FIG. 5 shows a structure according to this invention for electricmodulation of the intensity of reflected light at a linear array ofpoints.

FIG. 6 shows a structure according to this invention having a lineararray of optical image-forming means of the refractive type, each withan associated electro-optical element and with an electric circuit.

FIG. 7 shows another structure according to this invention having alinear array of image-forming means of the diffractive type, each withan associated electro-optical element and with an electric circuit.

FIG. 8 shows the arrangement of several structures as shown in FIG. 7into a two-dimensional array of image-forming means.

FIG. 9 shows another arrangement according to this invention ofindividual slabs each with a linear array of electro-opti cal elementsto produce a two-dimensional array.

FIG. 10 shows still another arrangement according to this invention ofindividual slabs each having a linear array of optical means and ofelectro-optical elements to produce a twodimensional array.

FIG. 11 shows the preassembly stage of structures with linear rows oflight-modulating elements into a two-dimensional array arrangement oftype of FIG. 10.

PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a silicon slab1 of edges a, b, 0 having PN-junction photocells 2, 2' between N-bulk 16and P-regions 28, 28' on its face 3 of area a x c exposed to incidentlight marked by the arrows 4 and 4'. The large face 5 of area b x ccarries an electric circuit 6 for amplification of the electric signalgenerated by 2 in response to 4. A diagram of circuit 6 is shown in FIG.2 and consists a resistor 7, N-channel insulated gate field effecttransistor 8, the connections 10, II and 12 to power supply 13 andoutput load 14. Illumination of 2 increases the potential of gate 15 of8 and thus increases current through output load 14 between terminals 10and 12.

The circuit of FIG. 2 is realized in FIG. by the NPN-structure of N-bulk16 with P-island 17 within which are N-islands l8 and 19, and theoverlayed silicon oxide 20 which carries metallized gate 15 andmetallized resistor 7. Contact lines 21, 22 and 23 extend over the oxideto connect 2 with 15 and terminals 11 and 12. Tenninal 10 is a contactto the N-body I6. Buried and exposed PN-junctions are indicated bydotted lines. The PN-junction between 16 and 17 isolates 2 from 8.Contact lines 21 and 22 are insulated from each other at theircrossover. Another identical structure is shown in FIGS. 1 and 2 andelements thereof are designated by primed numbers.

FIG. 3 shows the layout of a light-emitting PN-junction diode 30 withassociated circuitry according to this invention on slab 31 of P-typeGa-As-P. The light-emitting junction 30 borders the small surface 32 ofarea a x c of 31. Portions of large surface 33 of area b x c of 31 areoverlayed with an epitaxial N-layer of Ga-As-P, indicated by 34 and 35.N-layer 35 carries P-island 36 within which lies N-island 37, so that31, 35, 36, 37 represent a PNPN-semiconducting controlled rectifier 38.P-region 36 of SCR 38 is connected to N-region 34 of light emittingjunction 30 by path 39, which is insulated from substrate surface 33 byinsulating film 44. N-region 37 is connected by line 45 to capacitor 46,and over resistor 40 to terminal 41. Dielectric of capacitor 46 isinsulating film 47 and other electrode of capacitor is underlyingP-region 33. Film 47 also insulates 40 and 41 from P-substrate 31. Otherterminal of circuit is contact 42 to 31.

Application of positive DC potential at 42 with respect to 41 chargescapacitor 46 over resistor 40. As voltage across 46 builds up,PN-junction 30 connected to 46 over P-region 36 of SCR 38 becomesconducting and emits light. However, current through 30 triggers SCR 38which discharges 46 and cycle repeats itself. Result is a sequence oflight flashes 48.

Microcireuits and structures of light-emitting and lightsensingeIectro-optical components will not be detailed in the followingillustrations of the preferred embodiments, since such details would beobvious to one having ordinary skill in the art. We shall elucidate theinventive concept of the geometrical arrangement of arrays of suchmicrocircuits and eIectro-optical structures.

While examples so far have been monolithic design, i.e., eIectro-opticalelement and electric circuit were portions of same single crystal slab,my invention encompasses hybrid structure comprising electro-opticalelements and circuits of different materials. FIG. 4 shows a singlecrystal slab of P-type silicon 50 of side length a, b, having on one ofits major surfaces 51 of area b x c a set of planar microcircuits 52,52', 52" terminating at contacts 53, 53, 53". These microcircuits arelocated on N-type islands of 50 and are insulated from each other andfrom P-type bulk of 50 by PN-junctions 54, 54 and 54". A face of area ax c of 50 is overlaid with strip of P-type GaP 56 carrying on its uppersurface 60 the light-emitting PN- diodes S7, 57, 57", which areconnected to circuits 52, 52 and 52" by lines 58, 58' and 58",respectively. Other contact to diodes is through 56 and 50 by commonterminal 59. Sixtyone is an insulating film of SiO separating 58 fromP-substrates 50 and 56. Circuit 52 can be the SCR capacitor and resistorcombination of FIG. 3 or any one of many circuits commonly employed withlight-emitting diodes 57.

FIG. illustrates the arrangement according to this invention of an arrayof light-modulating elements each having associated electricalcircuitry. The light-modulating element is a liquid crystal cell asdescribed by Williams in US. Pat. No. 3,322,485. The silicon slab 76 issandwiched between insulating transparent walls 62, 63 extending beyondthe upper surface 64 of 76. Insulating transparent wall 65 and ceiling66 together with 62, 63 and 64 create a boxlike hermetically sealedenclosure 77 containing liquid crystal. Inside portions of upper wall 66are provided with transparent conducting stannous oxide coatings 67,67', etc. Contact lines 68, 68', etc., to 67 and 67' are located onouter surface of 62 and connect to planar microcircuits 69, 69' locatedon silicon surface 78 part of which is substrate to 62. Lines 70, 70'connect these microcircuits to external contacts 71, 71 Contact 72 to 76is common terminal for all liquid crystal cells. PN-junctions 73, 73'insulate N-substrates of microcircuits 69, 69' from P-bulk of 76.Circuit 69 can be a flip-flop or any other of the many circuits usefulin conjunction with liquid crystal cells. Incident light beams 74, 74are reflected into outgoing beams 75, 75' at surface 64 of silicon slaband intensity of outgoing beam 75 is modulated by voltage between 67 andsilicon substrate surface 64. This voltage is applied through terminals72 and 71 and processed by microcircuit 69 before reaching 67 throughlead 68.

The preferred embodiments described in FIGS. 1,3,4 and 5 contained a rowof photocells, light emitters or light modulators arranged along themajor edge c of a parallelepipedon with a row of corresponding circuitryon the adjoining major face.

The preferred embodiments to be described in FIGS. 6 and 7 contain a rowof optical image-forming elements arranged along that major edge c withassociated row of photoelectric and electric circuitry on the adjoiningmajor face. In FIG. 6, the optical image-forming elements are of therefractive type, and are located on said major face of area b x 0. Theyare designed for an incident (or outgoing) sheet of light. In FIG. 7,

the optical elements are of the diffractive type and are located on asmall face of area a x c. Diffractive optical image-forming means can beused instead of the refractive elements of FIG. 6 and refractive opticalimage-forming means can be used instead of the diffractive elements ofFIG. 7.

FIG. 6 shows a slab of generally P-type silicon with edges of lengths a,b, c whose surface 81 contains N-type islands 82, 82', 82" which carrymesa-type elevations 83, 83', 83" of P- silicon, representingPN-junction photoelectric sensors. Planar microcircuits 84, 84', 84"located on 82, 82' and 82" are electrically connected to said sensorsand to terminals 85. 85, 85''. Portions of 81 are covered withtransparent insulating films 86, 86', 86" of SiO, in the region betweensensors 83, 83', 83" and upper edge 87. Upper boundaries 88, 88', 88" of86, 86, 86" are curved to focus incident light beams 89, 89, 89" onsensors 83, 83', 83". PN-junctions between P- bulk of 80 and N-typeislands 82, 82', 82" provide insulation between microcircuits 84, 84'and 84".

FIG. 7 illustrates the arrangement of a row of optical elements 91, 92,93 located on the small face of area a x c of a rectangular N-typesilicon slab 100 of dimensions a b c. The side length a, b, c might beof the order of 2, I0 and 100 mils, respectively.

The optical elements 91, 92, 93 are halves of circular zone plates. Themajor planar surface 102 of area b x c carries a row of photocells 94,95, 96 located at image points of the zone plates. Associatedmicrocircuitry 97, 98 and 99 for photocells 94, 95, 96 is also locatedon surface 102. Each microcircuit extends essentially in b-directiontoward contacts 113, 114, 115. Associated circuitry 97, 98, 99 can beamplifiers or any suitable circuits. The circuits 97, 98 and 99 arelocated on P- type islands and are insulated from each other byPN-junctions 110, 111 and 112. Contact to this circuitry is made by themetal dots 113, 114 and 115 which are located at the bottom section ofarea a x c, opposite to the optical elements 91, 92 and 93. Othercontact is common lead 101 from photocells to N-body contact 116 andcontact 117 to the N-body of the wafer on side face of area a x b.

Photocells 94, and 96 must be responsive to radiation focused by 91, 92and 93 for which silicon is transparent. The face of area b x c whichdoes not carry circuitry 97, 98, 99 is coated by SiO layer 90 forinsulation between slabs when stacked as shown in FIG. 8 to provide atwo-dimensional array.

FIG. 8 shows slabs 100, 100" of type illustrated in FIG. 7 stacked sideby side on an insulating substrate 120. The substrate contains spacedprinted contacts lines 103, 104 and to which the contacts 113, 114, ofwafer 100 and corresponding contacts of wafers 100', 100", etc., aresoldered.

The lines 103, 104, 105 in conjunction with the contacts 117, 117',117", etc., provide X-Y-access for activating electrically an individualphotocell such as 94, 95 or 96. The photocell elements 94, 95 and 96 inFIG. 7 and 83, 83 and 83" in FIG. 6 can be replaced by light emittersproviding a light-emitting array. The microcircuit shown in these FIGS.can be any circuits known to be useful in conjunction with sensors orlight emitters, including gate circuitry to switch on or off theindividual electro-optical elements.

The arrangement of many slabs, each having a one-dimensional array ofelectro-optically active points on a small face into a two-dimensionalarray by stacking as shown in FIG. 8 for the slab of FIG. 7 can beutilized also for the slabs shown in FIGS. 1, 3,4,5 and 6.

FIG. 9 shows another preferred embodiment for arranging slabs havingone-dimensional arrays of photoelectric elements to providetwo-dimensional arrays, according to this invention.

In FIG. 9 there are three identical slabs 130, and 130". Slab 130 has arow of light-emitting elements 121, 122, 123 placed along the directionof the longest edge 0 and located on a major face of area b x c withassociated microcircuits 131, I32 and 133 on the same face. Eachmicrocircuit extends substantially in the b-direction, i.e., at rightangles from the direction of the row of light-emitting elements. Thisprovides for each microcircuit an area of about I x b, when l is thespacing of light-emitting elements. Each microcircuit is electricallyconnected to one of the light emitting elements 121, 122, 123 and to oneof the contacts 141, 142 or 143 (not shown). Other common contact is 125to bulk of slab 130. Rear surface of slabs in insulated by layer 124.Light emission form 121, 122, 123 occurs orthogonal to surface of area bx c on which emitters are located. Therefore, in stacking slabs 130,130, 130" to obtain two-dimensional arrays, slabs are displaced againsteach other along direction of b-edge to expose rows of light emittingelements 121, 122, I23; 121', 122', 123; 121", 122", 123", etc. Contacts125, 125, 125" provide Y-access lines. Contact 141 of slab 130 isconnected by line 151 to contacts 141, 141", etc. Similarly, contacts142, 142', 142" are connected by 152 and so forth to provide X-accesslines of an X-Y-address system.

The slabs are held together by fixing them to a vertical insulatingplate on rear surfaces of area a x b of slabs, now shown in figure.

Light-emitting elements 121, 122, 123 can be replaced bylight-modulating means or by photocells. Examples for these elements andfor associated microcircuitry can be taken from FIGS. 1, 3, 4 and 5 withappropriate modifications due to fact that light beams in FIG. 9 areemitted or incident substantially along direction of a-edge (i.e.,perpendicular to face of area b x c), while in previous FIGS. light wasincident along B-edge, i.e., perpendicular to face of area a x c.

In a variation of structure of FIG. 9, light emitting elements 121, 122,123 can be light-emitting PN-junction diodes, located on surface of areaa x c, and emitting light in direction parallel to a-edge. Thelight-emitting diodes can be of the mesa type, such as shown in FIG. 6for diodes extending from the b x c plane. Only a very small lateraldisplacement along bedge in stacking operation would now be required toexpose the light emitted parallel to the a x c face from the variousslabs. This displacement would be of the order of the height of mesaelevations of light-emitting diodes.

FIG. shows the stacking procedure of identical slabs I60, 160, 160"containing rows of optical focusing means 161, 612, 161', 161", etc.,photoelectric sensors 171, I72, 172', etc., and microcircuits I81, 182,182', etc., in circuit connection with these sensors.

Identical combinations of focusing means, sensors and microcircuits arelocated in each slab, spaced in direction of cedge. Slabs are stackedalong faces of area b x c, with displacement along b-direction to alignoptical means 161 of slab 160 with sensor 171' of slab 169'; Portion ofslab 160 is cut back to show this alignment. Optical means 161 is a zoneplate designed to focus monochromatic radiation for which underlyingbulk of slab 160 is transparent on sensor 171'.

In another preferred embodiment, sensor 171' and associated microcircuit181' are prepared on lower surface of slab 160 rather than upper surfaceof slab 160', Le, sensor and associated optical means are located onopposite surface of same slab and their alignment is then independent ofprecision in displacement of slabs by stacking operation.

The stacking principle demonstrated in FIGS. 9 and 10 is applicable alsoto light-modulating structures. A preferred embodiment is shown in FIG.11. The individual slab design has been modified somewhat from thecorresponding case of FIG. 5, since the light is now substantiallyincident and reflected in the direction of the a -edge. Components ofstructure in FIG. I] have been given numbers of FIG. 5 with digit 2 infront to simplify comparison. Only two slabs are shown in FIG. 11 in apreassembly stage. For final assembly, push lower left slab toward upperright slab along horizontal arrow.

P-type silicon slab 276 contains N-type island insulated by junction273. Microcircuit 269 on N-type island is connected by lead 268 toconducting layer 267 which is one contact to liquid crystal cell forelectric modulation of incident and reflected beams 274, 275. Walls ofliquid crystal cell of contact 267' on slab 276' is oxide coated face262 on slab 276 and transparent cover plate 266, and transparentinsulating plate 264'. Lower surfaces of 266 and 266' are provided withconducting transparent layers 200, 200 which are connected over a leadon a vertical sidewall (not shown) to P-bulk of slabs 276 and 276',respectively. Incident light beam 274 is reflected on 267 into lightbeam 275 and intensity of 275 is modified by electrical potentialapplied between contacts 272 and 271 fed over microcircuit 269 toelectrodes 267 and 200 of liquid crystal cell.

As there are many different circuits, and electro-optical and opticalcomponents which might be arranged according to my invention, it shouldbe understood that this invention is not limited by the preferredembodiments described, but encompasses all structures characterized bythe following claims.

Iclaim:

1. An electro-optical array for mutual conversion of radiative andelectric circuit energy, said array comprising a linear row of identicalelectro-optical elements and a row of identical semiconductingmicrocircuits, each said electro-optical element electrically connectedto one of said microcircuits, said electro-optical elements and saidmicrocircuits located on a slab shaped substantially likeparallelepipedon with edges of lengths a b c, so that i. at least aportion of each said electro-optical element is located on a surface ofarea a x 0;

ii. said microcircuits are located on a surface of area b x c;

and

iii. said radiation is coupled to said electro-optical elements byincidence on said surface of area a x c and directed substantiallyparallel to said surface of area b x c.

2. The electro-optical array of claim 1 whereby said electroopticalelements are electroluminescent light sources.

3. The eIcctro-optical array of claim 2 whereby said electroluminescentlight sources are light emitting PN-junction diodes.

4. The electro-optical array of claim 3 whereby said lightemittingPN-junction diodes are made from a compound of elements of the third andfifth columns of the periodic chart.

5. The electro-optical array of claim 3, whereby said lightemitting PN-junction diodes are contained in mesa-type elevations of said surface ofarea b x c of said slab.

6. The electro-optical array of claim 3 whereby at least part of saidlight-emitting PN junction diodes utilizes the same semiconductingmaterial as said microcircuits.

7. The electro-optical array of claim 1 whereby said electroopticalelements modify the intensity of incident light by application of anelectrical signal generated by said microcircuits.

8. The structure of claim 7 whereby said electro-optical elements whichmodify the intensity of said light are liquid crystal cells.

9. The structure of claim 8 whereby said liquid crystal cells extendalong a surface bounded by edges of lengths a and c of said block withsaid surface bounded by edges of lengths a and c being part ofthecontainer of said liquid crystal cells.

10. The electrooptical array of claim 1 whereby said electro-opticalelement includes an electro-optical component and an optical componentfor focusing said radiation on said electro-optical component, saidoptical component located on said surface of area a x c and saidelectro-optical component located on said surface of area b x c.

I]. The electro-optical array of claim 10 whereby said optical componentis a diffractive image-forming means.

12. The electro-optical array of claim 1 whereby said electro-opticalelements are photocells.

13. The electro-optical array of claim 12 whereby said photocells aresemiconducting photocells using the same semiconducting material as saidmicrocircuits and being monolithically integrated with saidmicrocircuits.

14. The electro-optical array of claim I whereby said slab comprisessingle crystal silicon and said microcircuits are planar microcircuitson said single crystal silicon.

15. The electro-optical array of claim 1 whereby each said microcircuitoccupies substantially a rectangular area on said surface of area b x c;the minor edge of said rectangular area being of a length of the sameorder as the spacing of said identical electro-optical elements; and themajor edge of said rectangular area extending substantially in thedirection of said edge of length 1;. 5

t F t i t

1. An electro-optical array for mutual conversion of radiative andelectric circuit energy, said array comprising a linear row of identicalelectro-optical elements and a row of identical semiconductingmicrocircuits, each said electro-optical element electrically connectedto one of said microcircuits, said electro-optical elements and saidmicrocircuits located on a slab shaped substantially likeparallelepipedon with edges of lengths a<<b<<c, so that i. at least aportion of each said electro-optical element is located on a surface ofarea a x c; ii. said microcircuits are located on a surface of area b xc; and iii. said radiation is coupled to said Electro-optical elementsby incidence on said surface of area a x c and directed substantiallyparallel to said surface of area b x c.
 2. The electro-optical array ofclaim 1 whereby said electro-optical elements are electroluminescentlight sources.
 3. The electro-optical array of claim 2 whereby saidelectroluminescent light sources are light emitting PN-junction diodes.4. The electro-optical array of claim 3 whereby said light-emittingPN-junction diodes are made from a compound of elements of the third andfifth columns of the periodic chart.
 5. The electro-optical array ofclaim 3, whereby said light-emitting PN-junction diodes are contained inmesa-type elevations of said surface of area b x c of said slab.
 6. Theelectro-optical array of claim 3 whereby at least part of saidlight-emitting PN junction diodes utilizes the same semiconductingmaterial as said microcircuits.
 7. The electro-optical array of claim 1whereby said electro-optical elements modify the intensity of incidentlight by application of an electrical signal generated by saidmicrocircuits.
 8. The structure of claim 7 whereby said electro-opticalelements which modify the intensity of said light are liquid crystalcells.
 9. The structure of claim 8 whereby said liquid crystal cellsextend along a surface bounded by edges of lengths a and c of said blockwith said surface bounded by edges of lengths a and c being part of thecontainer of said liquid crystal cells.
 10. The electro-optical array ofclaim 1 whereby said electro-optical element includes an electro-opticalcomponent and an optical component for focusing said radiation on saidelectro-optical component, said optical component located on saidsurface of area a x c and said electro-optical component located on saidsurface of area b x c.
 11. The electro-optical array of claim 10 wherebysaid optical component is a diffractive image-forming means.
 12. Theelectro-optical array of claim 1 whereby said electro-optical elementsare photocells.
 13. The electro-optical array of claim 12 whereby saidphotocells are semiconducting photocells using the same semiconductingmaterial as said microcircuits and being monolithically integrated withsaid microcircuits.
 14. The electro-optical array of claim 1 wherebysaid slab comprises single crystal silicon and said microcircuits areplanar microcircuits on said single crystal silicon.
 15. Theelectro-optical array of claim 1 whereby each said microcircuit occupiessubstantially a rectangular area on said surface of area b x c; theminor edge of said rectangular area being of a length of the same orderas the spacing of said identical electro-optical elements; and the majoredge of said rectangular area extending substantially in the directionof said edge of length b.